Agricultural planters are commonly used implements to plant seeds in soil. An agricultural planter can include a chassis that carries seed and/or chemical storage tanks, a hitch mechanism that attaches to a tractor or other implement pulled by a tractor, a toolbar, and row units attached to the toolbar. The planter can also include a pneumatic system carried by the chassis that supplies pressurized air to transport the seeds or other particulate from the storage tanks to the row units. The planter may additionally include marking devices in the form of a marking disc and one or more marker arm(s) connected to the lateral ends of the toolbar. The marking devices can be automatically and individually raised and lowered by a respective lift assembly, such as a hydraulic cylinder. The marking devices create a line, e.g. a furrow, in the field which illustrates a marker of the position of the planter as it traverses the field. This marker can be used by the operator to more easily align the planter during subsequent passes down the field. Thereby, the operator can properly align the planter so that the planter does not reseed an area or create a gap between a previously planted row and a new row. The marker arms of the marking devices can be folded into a stored position in which the arms rest on top of the toolbar or unfolded into an operational position in which the marking devices can mark a line in the field.
Generally, the outer marker arms have the ability to swing freely in the stored position. Thereby, the outer marker arms can become unfolded when the planter undergoes certain movements, for example, when the planter tilts up and down or side-to-side, performs fast end-of-field turns, and/or suddenly stops. If the outer marker arms undesirably unfold out of their respective stored positions, the outer marker arms may hit and damage another structure, such as the seed tanks, chemical tanks, trees, etc. Still further, the undesirable unfolding of the outer marker arms can result in damage to the outer marker arms themselves.
What is needed in the art is a cost-effective device to secure the marker arms in their respective stored positions.